1. Field of the Invention
The present invention relates to a method of efficiently reporting location technology in a mobile wireless access system supporting location-based service between a mobile terminal and a base station.
2. Related Art
With an increase of users who want to transmit and receive data while moving, Location Based Service (LBS) is recently emerging as one of the major services in the field of mobile communication. The LBS is service for providing various pieces of information pertinent to the location of a user while moving to the user rapidly and conveniently through wireless and wired communications. Not only IEEE 802.16m, but also various communication standards pertinent to the LBS have been established. The LBS is called LoCation Service (LCS) in the 3rd Generation Partnership Project (3GPP) and called Mobile Location Service (MLS) in Open Mobile Alliance (OMA).
In order to provide the LBS, wireless location technology is required. The wireless location technology includes a method using a satellite signal depending on a signal for the location, a method using a mobile communication signal, and a hybrid scheme using the two methods. Meanwhile, the wireless location technology is divided into a mobile-based mode in which the final location is determined or confirmed by a mobile terminal and a mobile-assisted mode in which the final location is determined or confirmed in a network, depending on the subject which determines the final location.
The method using a satellite signal is the same technology as a Global Positioning System (GPS), and currently commercialized technologies can include GPS location technology using a GPS satellite network by U.S.A.
The method using a mobile communication signal includes a method of measuring Timing of Arrival (TOA) between a mobile terminal and a base station, a method of measuring Time Difference of Arrival (TDOA) from two different base stations, and a method of a mobile terminal measuring the Direction of Arrival (DOA) or the Angle of Arrival (AOA) of a signal.
A mobile terminal reports location information, such as TDOA information and TOA information, to a base station using wireless location technology used by the base station. The base station measures the location of the mobile terminal on the basis of the location information reported by the mobile terminal. Here, the method of a mobile terminal reporting location information includes a method of reporting location information after a lapse of some time and a method of reporting location information when a base station requests the location information. However, in the two methods, unnecessary reports are generated when the move speed of a mobile terminal is slow or when a mobile terminal is in an idle mode. Accordingly, there is a need for a method of providing LBS when a mobile terminal is in a connected state or an idle state while reducing overhead.